Telegraphy.



P'ATENTED SEPT. 26, 1905.

P. w; JONES.

TELEGRAPHY.

APPLICATION FILED FEB. 7. 1905.

Mm W PATENT OFFICE- FRANCIS W. JONES, OF NEW YORK, N. Y.

TELEGRAPHY.

To all whom it may concern:

Be it known that I, FRANCIS W. Jones, a citizen of the United States, residing in the city of New York, county and State of New York, have made certain new and useful Improvements in Telegraphy, ofwhich the following'is a Specification.

' My invention relates to that form of multiplex telegraphy in which a simple Morse cir cuit has superposed upon it rapid alternations or impulses ofopposite polarity, the second set of signals being formed by varying said alternations or impulses.

The object of my invention is to provide an arrangement of apparatus which may be used upon more extended circuits and in which the alternating-current impulses are more com- .pletely utilized and more effective, the signals being stronger and firmer than in any arrangement heretofore known or used.

In a simple Morse circuit signals are produced by varying a normal current of one polarity, and an independent set of signals is also transmitted by varyingimpulses of rapidlyalternating polarity. The arrangement of such a circuit with straight or continuous current generators at opposite ends of the line and alternating-current generators at each station, including way-stations on branches connected to the main line inductively by a condenser, the set of Morse instruments in the main line being bridged by a series of branch circuits each containing a condenser, is old and well known. At the stations containing an alternating-current generator as heretofore arranged the generator and transmitter are in one branch and the receiving instrument is in a second branch, both being connected in parallel to one plate of the con denser. It results from this that a portion of the'transmitted current impulses are uselessly employed. The current impulses when transmitting being employed in operating the receiving instrument at the sending-station are deflected orwasted so far as their influence in signaling the distant station is concerned.

My improvement consists in arranging the transmitter so that when operated the receiving branch shall be open when the transmitting branch is closed and the transmitting branch shall be open when the receiving branch is closed, the latter being the normal or resting condition.

The accompanying drawing illustrates my invention. a

L is a main telegraph-line connecting the Specification of Letters Patent.

Application filed February 7, 1905. Serial No. 244,552.

' Patented Sept. 26, 1905.

stations m and n, at each of which there is a main straight-current generator 22, a resistance '24, a relay 3, a key 2, and an impedancecoil 4:. The Morse instruments 2 and '3 are bridged by a branch circuit.5, containing a condenser. The equipment of the stations on and n is identical, and signals are exchanged by breaking the normal straight current by opening and closing the transmitting-key2.

;The stations at and?) may be connected-at any points on the line andgare equipped for exchanging a separate and distinct set of signals by varying the duration of a wave-currentthat is, a current from an alternatingcurrent generator. The instruments at one station are duplicates of those at the other.

Referring to station a, there is a branch wire 40 connected to the line Land to one plate of the condenser 6. The second plate of condenser 6 is'connected to two parallel branches25and 26, which in turn are connected to the ground 21 successively by the operation of the transmitter t. In the branch 26 is included the coil of receiving apparatus or 'telephone 7 having a vibrating diaphragm Sand a vibratory contact or jockey 9. The

elements 8 and 9'form a circuit-breaker in the local circuit of battery 11, containing the coil 10 of a repeating-sounder. This sounder 10 on its back contact 14 closes thecircuit of battery 13 through the sounder-magnet 12.

There is an alternating-current generator 15 of an inductorium and the circuit-breaking points 33 34 of transmitter 16. In the ground branch circuit 25 is the secondary 17 of the inductorium referred to and circuit-breaker 31 32, operated by the transmitter 25. break-points 30 32 are in the receiving branch 26. The transmitter t includes an operatingmagnet 18 in the circuit of battery 20, which includes the hand key 19. Normally the transmitter t stands in the position shown, and the branch 26, containing the receiving; telephone 7, is closed at the circuit-closer 30-32 to the ground 21. In transmitting from a station like a when the key 19 is closed magnet 18 attracts the lever of transmitter t, contact is broken at 30 32, thus opening the receiving branch 26, and closed at 31 32, thus The completing the branch 25, containing the alterator 15 to become effective in the coil 17. In

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the operation of transmitting from station a When the key 19 is closed the receiving branch 26 is opened just prior to closing transmitting branch 25. It results from this that the full effect of the current impulses generated in coil 17 are effective in the branch 40 and line L and are not divided or Wasted in the branch circuit 26, as has heretofore been the case.

What I claim, and desire to secure by Letters Patent, is-

1. The combination of a suitable telegraphline connecting separated stations, and at two or more stations means for signaling by dividing short and rapid alternating-current impulses into groups of varying length, said means consisting of tWo branch circuits connected With the main line by a condenser common to both branches, a suitable receiving instrumentin one of said branches, a constantlyoperating source of short and rapid current alternations connected With the other branch, a transmitting device connected to both of said branches and arranged to open the receiving branch when the transmitting branch is closed, and vice versa.

2. The combination oi a suitable telegraphline connecting separated stations and two or more stations having means for signaling by dividing short and rapid alternating-current impulses into groups of varying length, said means consisting of two branch circuits connected with the main line by a condenser common to both branches, at suitable receiving instrument in one branch, a constantly-opcratingsource of short and rapid current impulses inductively connected with the other branch, a transmitting device connected to both said branches arranged to open the receiving branch When the other branch is closed and vice versa.

FRANCIS \V. JONES.

Witnesses:

JOHN F. CLEVERDON, V 'lHnonoRE L. GUYLER, Jr. 

